394432109 has 2 divisors, whose sum is σ = 394432110. Its totient is φ = 394432108.

The previous prime is 394432097. The next prime is 394432111. The reversal of 394432109 is 901234493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 373069225 + 21362884 = 19315^2 + 4622^2 .

It is a cyclic number.

It is not a de Polignac number, because 394432109 - 2²⁰ = 393383533 is a prime.

It is a super-2 number, since 2×394432109² = 311153377220375762, which contains 22 as substring.

Together with 394432111, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (394432139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197216054 + 197216055.

It is an arithmetic number, because the mean of its divisors is an integer number (197216055).

Almost surely, 2^394432109 is an apocalyptic number.

It is an amenable number.

394432109 is a deficient number, since it is larger than the sum of its proper divisors (1).

394432109 is an equidigital number, since it uses as much as digits as its factorization.

394432109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 394432109 is about 19860.3149270096. The cubic root of 394432109 is about 733.3715990822.

The spelling of 394432109 in words is "three hundred ninety-four million, four hundred thirty-two thousand, one hundred nine".